Date: Sat, 17 Dec 2016 18:40:16 +0100
From: Jiri Olsa <jolsa@redhat.com>
To: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: ast@fb.com, peterz@infradead.org, lkml <linux-kernel@vger.kernel.org>,
        acme@kernel.org, alexander.shishkin@linux.intel.com, mingo@redhat.com,
        daniel@iogearbox.net, rostedt@goodmis.org,
        Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>,
        ebiederm@xmission.com, sargun@sargun.me,
        Aravinda Prasad <aravinda@linux.vnet.ibm.com>,
        brendan.d.gregg@gmail.com
Subject: Re: [PATCH v4 2/3] perf tool: add PERF_RECORD_NAMESPACES to include
 namespaces related info
Message-ID: <20161217174016.GA722@krava>
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 <148182704002.5314.9908823892714757426.stgit@hbathini.in.ibm.com>
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On Fri, Dec 16, 2016 at 12:07:20AM +0530, Hari Bathini wrote:

SNIP

> +
> +int thread__set_namespaces(struct thread *thread, u64 timestamp,
> +			   struct namespaces_event *event)
> +{
> +	struct namespaces *new, *curr = thread__namespaces(thread);
> +
> +	new = namespaces__new(event);
> +	if (!new)
> +		return -ENOMEM;
> +
> +	list_add(&new->list, &thread->namespaces_list);
> +
> +	if (timestamp && curr) {
> +		/*
> +		 * setns syscall must have changed few or all the namespaces
> +		 * of this thread. Update end time for the namespaces
> +		 * previously used.
> +		 */
> +		curr = list_next_entry(new, list);
> +		curr->end_time = timestamp;

hi,
couldn't you use just the curr you got from thread__namespaces?
why to retrieve it again via 'new' pointer?

thanks,
jirka